I now have the marriage certificate for Thomas Holliday and Mary Ann Cressy. They were married 28 March, 1846 at the Parish Church, St. Clement Danes, Middlesex.
Thomas listed as 'full age', bachelor, mariner
father John Holliday, draper, living at 9 Bisterne Place, Poplar
Mary listed as 'full age', spinster
father John Duncan Cresey, master mariner, living at 1 Thanet Place
witnesses were Ann Smith, Jno. D. Cresey, E. Cresey
I have found Mary's mother in the 1851 census, but I can't seem to find anyone else. I expect Thomas H. and John C. were away at sea quite a bit.
Any ideas where I can go from here?